This air conditioner (100) comprises: an infrared sensor (3) that can detect temperature without contact; a storage unit (31) that stores thermal image data (20) acquired from the temperature detection results of the infrared sensor (3) and laundry drying location data (21) indicating the location where laundry has been hung to dry; and a control unit (30) that determines when laundry has been hung to dry by way of creating difference data indicating a temperature difference on the basis of two pieces of sequential thermal image data (20) and comparing the difference data and the laundry drying location data (21) and that starts operation in a clothes drying mode on the basis of determination results.